Wisconsin Gov. Scott Walker, once a top contender in the GOP race for president, peaked too early, then played it safe, and that's what tanked his campaign, columnist Charles Krauthammer said following Walker's exit from the campaign on Monday.

"When he peaked early, he was way out ahead of that one great speech he made in Iowa," Krauthammer said on Fox News Channel's "Special Report." "He then played safe. When he got a difficult issue like subsidies for biofuels in Iowa, he fudged, he said, 'I'm not going to talk about certain issues.'"

Walker led early in Iowa, but saw that lead eroded as businessman Donald Trump entered the race. A CNN/ORC poll released on Sunday showed Walker's support had slipped to less that one-half of one percent nationally after his performance at Wednesday's second GOP debate.

"When he knew he disappeared in Iowa, it was over," Krauthammer said.

Walker said in his resignation announcement that he urged others low in the polls to follow his lead so that the opposition to "the front-runner" Donald Trump could coalesce from the currently crowded field.

"In a way, it's kind of patriotic," Krauthammer said.

Krauthammer himself has been a critic of Trump's bombastic style, and has been the brunt of Trump's criticism for doing so.

"Special Report" host Bret Baier said he was told by a friend of Walker that the governor didn't run on who he is, but as who he thought people wanted him to be – especially in Iowa where he once led.

"And that was his demise. He could never get traction even from the start," Baier said.

Ron Brownstein, editor of National Journal, echoed that on CNN's "The Situation Room with Wolf Blitzer," saying that Walker started strong, running on business, economics, standing up to public employees and cutting taxes, then decided to appeal more to cultural conservatives.

"So he moved right on immigration and moved right, supported a constitutional amendment to overturn the gay marriage decision and alienated upscale supporters," Brownstein said.

Fox News' Brit Hume said the Walker seen in the debates looked nothing like the fighter who took on public employee unions.

"The man in the debate seemed retiring, he seemed not to have a lot to say, he didn't use his full-time particularly in the first debate," Hume said. "In the second debate, he didn't get called on much so he failed to make a splash."

Wisconsin Gov. Scott Walker, once a top contender in the GOP race for president, peaked too early, then played it safe, and that's what tanked his campaign, columnist Charles Krauthammer said following Walker's exit from the campaign on Monday.
When he peaked early, he...